JANUARY 26th: A source tells Mark Murphy (via Twitter) that Johnson will probably get a second 10-day deal.

JANUARY 17th, 11:19am: The team announced the signing, via press release. Having waited an extra day to make the deal official means the club gets to squeeze in an extra game for Johnson, whose contract won’t expire until after Boston’s game against the Nets on January 26th, as Steve Bulpett of the Boston Herald points out (Twitter link).

THURSDAY, 12:44pm: The Celtics plan to sign Johnson on Friday, according to Wojnarowski (Twitter link).

11:14am: Chris Johnson and the Celtics are finalizing a deal, and the expectation is that he’ll sign a 10-day contract, tweets Chris Forsberg of ESPNBoston.com. Adrian Wojnarowski reported overnight that Johnson was in town for a workout with the club. The small forward from Dayton is not to be confused with the Chris Johnson from LSU who played with the Celtics during the 2010/11 season. The move brings Boston’s roster to 14 players.

Johnson has been averaging 19.4 points and 6.8 rebounds in 37.2 minutes per game for the D-League’s Rio Grande Valley Vipers this season, after spending training camp with the Nets. His only official NBA action came on a pair of 10-day contracts with the Grizzlies last season, when his averages were 3.6 PPG, 1.4 RPG and 12.8 MPG.

The Celtics traded away Jordan Crawford and MarShon Brooks yesterday, and they’ve excused Keith Bogans from the team, so Johnson will bolster the team’s dwindling wing depth. Boston will have an open roster spot even after adding Johnson, and Wojnarowski’s report seemed to suggest the team might be working out other players.

Johnson is a client of Pinnacle Management Corp., as our Agency Database shows.